WASHINGTON — Last week, top US defense officials told Congress that if the Pentagon were allowed to bust its budget caps, it would save one aircraft carrier and tens of thousands of troop billets slated for elimination. But DoD’s new spending request — which stays under the cap for 2015 but exceeds the 2016-19 caps by a total of $115 billion — contains no money for the carrier and extra troops, according to a senior DoD official.

It’s unclear just what the $115 billion would pay for, if not for troops and the carrier. DoD has yet to release details of the future years defense plan (FYDP). But officials have said that it would go to prevent early retirements of other ships and aircraft.

DoD officials say they’re not talking out of both sides of their mouth. They say it’s simply the best they could do, given short-notice direction from the White House to craft a budget that exceeds the sequester spending caps.

They say their plan now allows for two distinct possibilities: one, to make drastic cuts if Congress refuses to end sequestration; or two, to save the carrier and ease the end-strength cuts if more funding is provided.

But Todd Harrison, an analyst with the Center for Strategic and Budgetary Assessments, notes a disconnect: “The department would need even more money or would have to find offsetting cuts in the budget to reach 440,000 in Army end strength, 182,000 in Marine Corps end strength, and 11 carriers.”

DoD officials concede they would have to rewrite the 2016-19 spending plan submitted with the 2015 budget request on Tuesday if they get the funding increase. “Yes, we will have to go find the funding in order to restore these forces,” the senior defense official said on Wednesday.

The official said DoD could easily move money between procurement, research-and-development and other accounts because the 2016-19 FYDP is non-binding.

“But we’re pretty sure we can do that,” the official said. “We know we can.”

All this has caused widespread confusion among even the most senior members of Congress and budget analysts who have spent their careers crunching numbers.

Sen. Carl Levin, D-Mich., chairman of the Senate Armed Services Committee, questioned Hagel and Pentagon Comptroller Robert Hale about the extra money on Wednesday. After a number of back-and-forth exchanges, Hale asked, “Does that help?”

“So the FYDP is not real,” said Gordon Adams, who ran defense budgeting during the Clinton administration and is now a professor at American University. “Abbott and Costello couldn’t have done it better.”

DoD’s 2015 budget request, sent to Congress on Tuesday, proposes to spend $496 billion in 2015 and a total of nearly $2.2 trillion in 2016-19. That does not include war funding.

Defense officials say their proposal allows the necessary long-term planning to shrink the military in a deliberate manner. Under the sequester caps, the Army will shrink from 510,000 to 420,000 troops and the Marine Corps from 189,000 to 175,000.

But Defense Secretary Chuck Hagel and other top defense officials have said that if Congress allows DoD to spend above the budget caps, they will halt the force structure reductions between 440,000 and 450,000 for the Army and at 182,000 for the Marine Corps. They will also keep in service a Navy carrier now slated for early retirement.

In a March 5 memo, Acting Deputy Defense Secretary Christine Fox told the top civilian and military leaders in the Army, Navy and Marine Corps to “program for” the end-strength levels proffered by Hagel.

“We must continue to be prepared, however, for funding below the FYDP,” Fox wrote. “Therefore, I want you to also be prepared to amend your submission if we receive indication, in time to inform FY 2016, that funding will remain at the current BCA caps.”

Fox also noted, “This budgeting process has been marked by uncertainty and irregularity, with changes to our spending assumptions that came late in the process.”

She stressed the need to be ready to rewrite the spending plan no matter which way Congress goes on the sequester limits. ■